Hydrogen, Fuel Cells, and Reality

Will fuel cells running on hydrogen soon propel our cars and solve all our fossil-fuel woes?We examine the facts behind the hype of the power source that helped carry men to the moon and may, many believe, soon doom the internal-combustion engin

You've probably seen the anchorman for your local TV news deliver the same breathless teaser: "Imagine buying a car that runs on an infinitely available supply of cheap fuel and emits nothing but drinking water from its tailpipe. How hydrogen-burning fuel-cell vehicles are going to revolutionize driving as we know it--film at eleven. "For sure, the promise of fuel cells makes for tantalizing copy. No wonder, then, that fuel cells have suddenly become the Holy Grail of the 21st century. Their proponents--including President George W. Bush, Democratic challenger John Kerry, top automakers, environmentalists, and vast numbers of ordinary citizens--speak with giddy optimism about the benefits of putting these wondrous devices, versions of which provide electricity for most NASA spacecraft, into our automobiles: no emissions to pollute the air, freedom from dependence on foreign oil, the efficiency of fuel-cell power, an everlasting source of energy that ends our greedy withdrawals from the earth's finite bank account of nonrenewable fossil fuels like oil, coal, and natural gas. In 20 years, they say, we'll all be happily scooting around in nontoxic, wallet-friendly electrolysis-mobiles--and the only ones complaining will be the oil sheiks and maybe the world's suppliers of bottled water.

But is the reality of fuel cells really so rosy? Detractors, among them engineers, atmospheric scientists, economists, and another camp of environmentalists, are equally adamant that fuel cells aren't the answer to our transportation prayers. They point to a range of concerns, including massive technological hurdles, the difficulties of manufacturing and storing vast quantities of hydrogen, enormous costs for building a hydrogen-delivery infrastructure, misinformation about hydrogen's environmental friendliness, and fears--valid or not--about driving in a world full of mini-Hindenburgs. Why chase extravagant and complex fuel-cell fantasies, argue the naysayers, when other transportation options, such as hybrids, offer a far more cost-effective and rational solution to our environmental and energy-supply concerns?

It's time we all took a moment to have a good look at the facts of this case. In the following pages, we'll review the specifics of hydrogen as a fuel, examine how fuel cells work, drive a fuel-cell prototype vehicle, and talk with authorities on both sides of the fuel-cell fence. Our aim is not to make definitive conclusions (even the world's leading fuel-cell experts clearly aren't unanimous in their thinking), but to bring some clarity to the debate--a fuel-cell reality check, if you will. After all, hydrogen may be lighter than air, but whether it and fuel cells deserve to be on our list of future transportation alternatives is proving to be a weighty issue indeed.

Shedding Some Light: Hydrogen FAQ What is hydrogen?The lightest element in existence. At sea-level atmospheric pressure, a cubic foot of hydrogen weighs just 0.09 ounce. Hydrogen sits in pole position on the Periodic Table of Elements, bearing atomic number 1.Where does hydrogen come from?Hydrogen is the most abundant element in the universe. Trouble is, most tiny hydrogen atoms within our reach are happily married to big, fancy carbon and/or oxygen atoms, and convincing them to leave and pair up with another boring H atom in liquid or gaseous H2 requires a considerable amount of energy.

How do we get hydrogen?The easiest and potentially cleanest way is called electrolysis: Dunk electrodes in water, apply electricity, and you get hydrogen gas bubbling off the negative electrode and oxygen from the positive one. But electrolysis is only as economical and clean as the electricity going in, which is to say "not very" in most of the world today. Consequently, of the nine million tons of hydrogen currently produced in the U.S. each year, 95 percent is generated using steam and heat to strip hydrogen atoms off methane gas. This process produces carbon dioxide (CO2), as do all similar methods of reforming coal and other hydrocarbons. Other processes show some long-term promise for producing low-cost, clean hydrogen, including reforming biomass feedstocks like corn-based ethanol (which can be carbon-dioxide neutral--releasing only as much CO2 as the plants consumed in the first place), and experimental methods like converting sugar water to hydrogen at around 400 degrees F using a nickel-zinc catalyst or starving green algae cells of sulfur to cause them to generate hydrogen.

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How suitable is hydrogen as a fuel?Hydrogen packs more punch in terms of energy per weight than any other fuel, but by volume it's one of the wimpiest. It produces little or no pollution at the "tailpipe." Because hydrogen offers no lubricity and is highly volatile, fuel-handling systems must be hardened and hermetically sealed. Generating hydrogen requires considerable energy input, and compressing or liquifying it requires a further input of energy equal to 10 or 30 percent of the hydrogen's energy content, all of which ranks it among the least convenient and practical of all transportation fuels.

Shedding Some Light: Hydrogen FAQ cont... What would hydrogen cost?A recent study by the National Academy of Engineering projected the future wholesale costs of hydrogen production and distribution. Centralized plants making hydrogen from natural gas or coal and piping it in compressed form currently charge about $2 per kilogram. (A kilogram of H2 roughly matches the energy in a gallon of gasoline, the wholesale cost of which the study identified as $1.12 for comparison.) Add to that another $1.50 for making liquid hydrogen. In the future, those costs should drop 40c a kilogram for compressed H2 and $1.30 for liquid H2. Making hydrogen at the filling station today costs about $3.50 per kilogram for natural-gas reformation and $6.50 for electrolysis; the study predicts those costs would drop to $2.30 and $3.90 in the future.How is hydrogen stored/transported?Today, hydrogen is compressed and delivered by pipeline in limited areas near large production facilities. For road or rail delivery within 200 miles, tube tanks of compressed gas are used, but for longer distances the hydrogen is usually liquefied and carried in cryogenically cooled tanks at -423 degrees F. As the hydrogen economy emerges, a network of pipelines like those used to distribute natural gas could be developed, and it may prove feasible to produce hydrogen from natural gas (in home garages for overnight refueling).

How do we carry hydrogen on board a car?Today, cylinders capable of handling hydrogen compressed to 5000 or 10,000 psi are the most technically feasible, but range is a problem in small, light vehicles. One kilogram of hydrogen has about the same energy content as one gallon of gasoline, but even at 10,000 psi, one kilogram of hydrogen takes up about one cubic foot of space--the same as 7.5 gallons of gas. A kilo of liquid hydrogen takes up just half a cubic foot, but must be kept at -423 degrees F in a superinsulated tank. Even in the best of these, the hydrogen boils off at a rate of up to three percent per day. High-pressure, insulated tanks tend to be bulky and difficult to package, as they must be cylindrical or torus (donut) shaped. Certain powdered metals will bond to and release hydrogen at low pressures and relatively high hydrogen densities in easily packaged shapes, but the metals themselves are heavy, require large amounts of heat to release the hydrogen, are slow to refuel, and/or require heavy cooling energy during refueling. Liquid sodium borohydride can be pumped into a conventional fuel tank to solve some of these problems, but once depleted of its hydrogen, the leftover sodium metaborate must be stored on board and returned to the refinery for recycling. Getting carbon nanotubes to absorb hydrogen is another drawing-board concept that may one day prove useful. The industry has more or less abandoned the notion of refueling with gasoline or methanol and equipping cars with on-board refineries to extract hydrogen.

How would a hydrogen gas station work?Expect gassing up with hydrogen to be a much more sanitary and more automated task than you're used to with gas and diesel. Standards are under development for an intelligent filler neck integrated with a ground strap (to prevent static electric sparks), and a communications link between the tank and the pump to monitor pressures and temperatures. Robotic refueling has also been demonstrated. The goal is to be able to refuel within five to 10 minutes, but fast-filling compressed tanks causes temperatures (and consequently pressure) to rise, making it difficult to fill the tank completely.

How safe is hydrogen?Hydrogen is highly flammable over a wide range of concentrations, but upon release it rises four times faster than natural gas, whereas gasoline vapors and propane can gather in strong concentrations on the ground. These are the reasons we know that the Hindenburg's hydrogen didn't explode as commonly believed. Some of it burned, but most dispersed as proven by the 37-second burn time and the small number of casualties (also, hydrogen is nonluminous--all but invisible--when it burns). The fuel content of the Hindenburg's hydrogen was equal to 18,000 gallons of gasoline--imagine that explosion! Hydrogen is also nontoxic, unlike most hydrocarbon fuels.

Water & PowerHow a fuel cell works--and produces both of the aboveThink of a fuel cell as an electrochemical dating service that helps lonely hydrogen (H) atoms hook up with single oxygen atoms (O), creating water (H2O). More important for power purposes, the process also produces heat and electricity. In a sense, a fuel-cell vehicle works like a battery-electric car, except that it's able to recharge with hydrogen and oxygen instead of electricity.

There are several different types of fuel cells, each of which manages to liberate hydrogen atoms from some type of fuel and rob them of their electrons, which then flow through an electrical circuit to perform some useful work (before being mated, along with the naked hydrogen protons, to an oxygen atom to form water).

NASA started using alkaline fuel cells in the Apollo spacecraft. These use a potassium hydroxide electrolyte and can operate at room temperature with 60-to-70-percent electrical efficiency, but they require pure hydrogen and pure oxygen (no carbon dioxide) to function. Other systems with similar efficiency can strip hydrogen away from natural gas, coal gas, or other hydrocarbons using phosphoric acid, molten carbonates, or solid oxides as an electrolyte, but these all operate at high temperatures (390 to 1830 degrees F), and they're slow to react to changing electrical demand, so they're best used as stationary power generators.

That leaves the PEM (proton-exchange membrane or polymer-electrolyte membrane) fuel cell as the best choice for automotive use. It requires pure hydrogen but can accept filtered air as the oxidant. The electrolyte in a PEM is a thin sheet of Teflonlike polymer infused with sulfonic acid molecules that, when wetted with water, acts like plastic battery acid, allowing hydrogen protons to pass through while keeping the hydrogen gas and air apart. The anode and cathode on either side of this membrane are coated with precious metals, usually platinum, to help dissociate the electrons from the hydrogen and to recombine the water molecules. Electrical efficiency of between 40 and 60 percent is possible within a temperature range of -4 to 200 degrees F. A special type of PEM can remove hydrogen directly from liquid methanol, but its electrical efficiency is half that of a pure-hydrogen-fueled PEM fuel cell and is therefore not yet practical for cars.

Leaving In A HuffThe unusual sounds and sensations of driving a fuel-cell vehicleA hydrogen-fuel-cell car is basically a battery-electric vehicle that's getting its electrical energy by other means. It's not surprising, then, that FC vehicles and battery-electrics share a lot of similarities in driving feel--particularly under acceleration. Punch the accelerator pedal in an FC, and you're awash in the whirs and howls of an electric motor driving reduction-gear teeth, with none of the stepped shifts we've all grown accustomed to with conventional transmissions (the high-rpm capability of electric motors renders them unnecessary).

However, because a fuel-cell stack's electrical output intrinsically lags behind your right foot's request for acceleration, FC vehicles usually require some type of supplemental energy reservoir to fill the gap. Most commonly, this is via an advanced battery type such as nickel-metal hydride. But in Honda's FCX fuel-cell prototype (a handful of which began doing experimental duty on the streets of Los Angeles in 2002), that role is performed by an entirely different type of energy-storage device called an ultracapacitor. As with pure battery electric cars, this storage device does double duty: In addition to being an acceleration gap-filler, it's a warehouse for electrical energy recovered during braking. Because of the intense competition for space among the various components that make a fuel-cell vehicle work, this battery (or, in the FCX's case, ultracapacitor) is of rather modest size. On occasions when the ultracapacitor becomes filled with braking electricity, the result can be irregular braking effort.

At rest, two sounds dominate your auditory experience: the woosh of blower noises emanating from the cooling fans and the huff of the air pump that's feeding pressurized air to the fuel-cell stack (a sound that, under firm acceleration, can rise to a wail.) Under normal driving conditions, you'd probably note the suspension's firm springing, a consequence of the considerable weight added by an FC car's myriad components. Otherwise, the driving experience of a fuel-cell car is remarkably conventional--that is, except for the small puddle of exhaust water you might notice beneath your tailpipe after you step out.

Cell MatesPromising rival technologies vying with fuel cells to become the dominant power source for cars of the futurePlug-in HybridsOne of the touted advantages of the hybrid vehicle is that, unlike a battery-electric car, you don't have to plug it in. Now, the Plug-In Hybrid Electric Vehicle touts just the opposite. Depending on the capacity of its expanded battery pack, a PIHEV can travel from 20 to 60 miles producing no tailpipe emissions at all. Go beyond the batteries' range, and the PIHEV's internal-combustion engine would fire-up to maintain the batteries' charge, taking you any distance you like (at least until the gas tank runs dry). With the IC engine to augment you during the day, the PIHEV can plug-in to off-peak (and cheaper) electricity while you sleep. Gas station visits would be rare indeed.

Alternate FuelsAmong these are fuels that could reduce our dependency on scarce (or unreliable) oil sources, those that help the environment, or ideally both. Natural gas is a clean-burning hydrocarbon that might be a good match for hybrids; hybrids offer excellent range--a perfect offset for the low-energy density of this compressed gaseous fuel. Another alternative is biodiesel, which is produced from biologically sourced fats or oil (such as soybean oil). Alone, or mixed with conventional diesel, it can reduce atmospheric carbon by recycling it via a natural carbon-cycle (from plants to fuel to the air and back to plants again). Plus, the diesel engine offers legendary efficiency.

Battery-Electric VehiclesIs the battery-electric car dead? Not according to some experts, who claim that car manufacturers and legislators lost interest in the battery car just when battery technology started to take off. Among the most promising are new-generation lithium-ion or lithium-polymer batteries that could offer vehicle ranges of 300 miles or more. Daytime recharging time would still be an issue, but only for significant trips.

An Idea Catching FireWhy not just burn the hydrogen?Fuel cells are expensive, hard to start in sub-zero weather, and susceptible to fuel contamination, so why not just burn the hydrogen instead?That's the thinking at BMW, Mazda, and elsewhere, at least for the near term. Hydrogen is highly flammable and will burn at concentrations ranging from four to 74 percent, producing some oxides of nitrogen (NOx) but only trace amounts of carbon dioxide and hydrocarbon emissions (from burning the oil film off the cylinder walls). Hydrogen burns clean, but not to zero-emissions standards.BMW and Mazda believe dual-fuel gas/H2 engines could be marketable while the hydrogen infrastructure is under development. BMW began experimenting with hydrogen engines in 1978 and has built demonstration fleets of hydrogen V-12-powered 750hL sedans and, more recently, a 4.4-liter V-8 745h. Mazda has shown numerous hydrogen-fueled rotary-engine concepts since 1991.

BMW uses special port fuel injectors and a variable-pressure fuel rail to inject a mixture that remains lean enough to greatly limit the amount of NOx formed in the cylinders. The 750hL V-12s built in 2000 produced 201 horsepower running on hydrogen, good for a 9.6-second 0-to-62-mph run with a range of about 180 miles on just under five gallons of liquid hydrogen. The newer Valvetronic V-8 generates 181 horses, achieving similar range and performance. (The gasoline variants of these engines produce 326 and 325 horsepower, respectively.)

Mazda claims its rotary engine is inherently better suited to hydrogen operation. Because the intake, compression, and combustion events take place in different areas of the rotor housing, the intake chamber remains much cooler, which prevents backfiring and knock. There's also sufficient space to install two hydrogen direct injectors. The Renesis Hydrogen RE engine produces 110 horsepower on H2, 210 when running on gas.

Ford's 2.3-liter hydrogen-fueled four-cylinder Model U concept-car engine develops almost the same output as a similar gasoline engine, but gives up the dual-fuel capability in the bargain. Ford upped the compression ratio to 12.2:1, while a centrifugal supercharger adds 14.5 psi of boost. To prevent knock, the charge air passes through both an air-to-air and an air-to-air-conditioner refrigerant cooler. Doing all this, and running slightly richer than the ideal 50/50 hydrogen/air mix, achieved equivalent peak torque to the 2.3-liter gas engine.

Running on hydrogen extends engine life and reduces maintenance, as no carbon builds up in the combustion chamber or on the spark plugs and the blow-by gases are so clean that the oil rarely needs to be changed (just topped up periodically). Such engines start and run well at low temperatures, are tolerant of "dirty" hydrogen fuel, and would be comparatively easy to tool up. That's where the good news ends. An extensive study of well-to-wheel energy efficiency conducted at Keio University in Japan shows hydrogen internal combustion to be among the least efficient of all advanced technology powertrains, owing largely to the energy required to produce and compress or liquefy the hydrogen.

Fuel Cells: Pro And ConFour experts speak outPRO: Amory B. LovinsAmory B. Lovins, 54, is a Harvard- and Oxford-educated physicist who cofounded the Rocky Mountain Institute (www.rmi.org), a not-for-profit think tank with a staff of 50 whose mission is, in large part, to help create and publicize sustainable energy sources. Lovins also founded Hypercar, dedicated to the design of ultraefficient vehicles of the future.Lovins has been studying and writing about hydrogen and fuel-cell technology since the 1980s, and his 2003 technical paper, "Twenty Hydrogen Myths," may be the most-quoted source for those seeking to counter critics who insist that hydrogen is too expensive and dangerous to become America's source of sustainable energy. Examples: "Myth Number 7: We lack a safe and affordable way to store hydrogen in cars." Or "Myth Number 11: Manufacturing enough hydrogen to run a car fleet is a gargantuan and hugely expensive task. "Motor Trend: It's your position that while hydrogen fuel cells may well be the energy source of the future, to take maximum advantage of what hydrogen can do, the way we engineer and build vehicles must evolve.

Amory B. Lovins: You can build an extremely efficient car, and save most of the fuel you'd normally use, without using hydrogen. But once you've made a car like that, the business case for using hydrogen and fuel cells becomes robust. But it isn't really robust until you do that.

MT: There's substantial research being done into using hydrogen as a fuel source for internal-combustion engines, essentially as a gasoline replacement. Do you see much of a future in that?

AL: I think there would be niches where a hydrogen-powered internal-combustion engine would work, but due to the packaging and storage issue, I don't see it as very likely for a general market. If you had an efficient internal-combustion engine running on hydrogen as a hybrid, basically a hydrogen-fueled Toyota Prius, you'd get about a quarter of the range of gasoline for the same tank volume. You could package more tank volume and sacrifice some of the trunk, say, but it still gets pretty awkward.

MT: Regarding on-board storage, manufacturers seem to be using hydrogen tanks that operate at 5000 psi of pressure, with 10,000 psi in the future. Is that going to be a difficult concept to sell to the public?AL: The tanks are extraordinarily strong. Remember that the pressure inside makes them kind of rubbery in a crash. One manufacturer spent about a decade trying to destroy 5000-psi tanks every way it could think of and never got one to fail ungracefully. The issue with 10,000 psi tanks may be a little different. Using current materials, the space and weight penalties are significant enough that you have to ask yourself if it's worth it, or whether it would be better to put the money into lightening the platform rather than increasing the pressure.

MT: Is there anything that would help jump-start the move to hydrogen?

AL: If you really want to move quickly to a hydrogen economy, we need to combine the use of fuel cells as vehicle power and as stationary sources of power, so each helps the other happen faster.

Though we've couched this conversation mostly in terms of saving fuel, there are a lot of other reasons to go to hydrogen. Those include the flexibility in what you make it out of and what scale you make it in. And the ability for us to make an all-North American energy supply system and get off oil altogether, not just imported oil. And increased safety for the climate, if you do it right. And some rather startling value propositions, the most obvious being vehicle-to-grid where the first two million or so people to do this can basically pay for their car by using it as a powerplant when it's parked. Two million is enough to make fuel cells pretty cheap.

CON: Dr. Paul MacCreadyDr. Paul MacCready, the 78-year-old chairman of Aerovironment in Monrovia, California, gained worldwide notoriety for building the world's first successful human-powered aircraft, the Gossamer Condor. Since, his company has been responsible for GM's Sunraycer solar-powered vehicle, the battery-powered Impact (prototype for the EV1), and the high-altitude solar-powered Helios aircraft. The latter will potentially stay aloft for months at a time by creating and storing hydrogen during daylight hours for use in its fuel cells at night.

Motor Trend: Before dipping into the fuel-cell subject, what's the automobile's near-term picture look like to you?

Paul MacCready: In let's say five years, it'll be obvious that internationally we'll be on the down slope of the oil-production curve. Meanwhile, the number of vehicles on the road will still be rapidly climbing--most significantly due to China's growth. Consequently, I think prices will start going way up, and things are going to be traumatic. It's hard for us to think about this because we've always just had oil. It's always seemed infinite.

MT: But you think hydrogen is the answer?

PM: The biggest problem with the hydrogen economy is the cost. The hydrogen-fuel-cell approach got started by some enthusiasts who did studies without really understanding its economics and realities, and our government went along with it. If the United States focuses on the hydrogen-fuel-cell economy and actually puts the money into it that's needed to generate the hydrogen without producing pollution, the cost will be just staggering. From a practical standpoint, our company's real-world experience with currently available hydrogen fuel cells is that they hardly work at first and then take months to get operating properly. They're incredibly complicated, which the field has not let people know about. People think fuel cells are simple--they're not.

MT: What's the alternative?PM: Batteries have recently gotten good. Lithium batteries, as presently used in cell-phones and microcomputers, have about six times the energy per kilogram as the lead-acid batteries employed in the first electric vehicles. They're a little expensive at the moment, but the prices are quickly coming down. In two to four years they will be affordable for automobiles.

In fact, we're amazed at what's happening with them; there are lithium cells out there offering 220 W-hr/Kg [a measure of energy density] compared with the 60 to 70 you get from nickel-metal hydride. And they're probably going to 250 W-hr/Kg; some people are even working on 300-to-350 W-hr/Kg cells. At the 180-to-200 level, they're very good, but at 300-to-350, they'll take over. At first you'd probably use these cells in conjunction with an engine [i.e., in a hybrid vehicle] for those rare trips over 100 miles and employ the battery for everything shorter. But when they get cheap enough to take you 300 miles, that's probably the end of the gasoline engine. On a trip, you'd be able to go 300 miles, stop for coffee and a hot dog while you charge up, and then go another 200. That's 500 miles in a day.

PRO: Dennis WeaverThe public knows Dennis Weaver as the Emmy-winning actor whose television roles as Chester in "Gunsmoke" and Sam McCloud in "McCloud" guarantee him a place in the lore of American pop culture. Weaver also starred in the classic 1971 car movie, "Duel" (directed by a 23-year-old Steven Spielberg), as a hapless businessman driving a Plymouth Valiant across the desert, inexplicably pursued by an evil 18-wheeler. But in the past decade, Weaver's become a visible spokesman for alternative energy in general and hydrogen fuel cells in particular as the fuel source of the future. In May 2003, Weaver led the "Drive To Survive," a two-week cross-country caravan of alternative-fuel vehicles, from Los Angeles to Washington, D.C., and he made multiple public appearances in the 20-city tour of "Drive Hydrogen Home."

This summer, Weaver, 80, takes to the road again for "Dennis Weaver's International Hydrogen Drive 2004," where he'll lead a caravan of vehicles powered by hydrogen fuel cells from Los Angeles to Mexico to Canada (www.hydrogendrive.com).

Motor Trend: Is hydrogen the answer to easing our dependence on oil?Dennis Weaver: It's one of the answers. Hydrogen is one of the most plentiful elements in the world. It's everywhere. We can never use it up. And it's clean, so long as you create the hydrogen using clean energy sources, such as the sun, the wind, biomass, moving water. If you create it by using electricity from a coal-fired power plant, that's dirty hydrogen, and I think we're just spinning our wheels if we take that road.If we go to hydrogen, we could benefit in four different ways. One, we'd be able to stop trashing our planet because probably 90 percent of the environmental problems we have we can trace to our addiction to fossil fuels.

Two, it would give our economy a tremendous boost. Our economy has always been stimulated by new technology, by innovation, by new ways of doing things. When we went from the horse and buggy to the automobile, the automobile industry created a tremendous amount of new jobs we couldn't even foresee.

Three, it would bolster our national security. As long as we're dependent on foreign oil to support our economy, our economy is at risk and so is our national security. We should be able to support our own economy within our own borders.

And four, I think a global hydrogen economy--not just national, but global--would promote peace. In my opinion, most wars are fought over diminishing resources. Especially if that resource is extremely valuable, which we perceive oil to be.

MT: No one denies, though, that changing to a hydrogen transportation system will not be easy. Are you convinced that we can overcome the challenges, if we have to?

DW: Absolutely. You said the right words: "If we have to." But it's not an "if." We're going to have to change. Oil is simply not a resource that can be grown or manufactured. It's going to be gone. Some scientists are telling us it'll be 30 or 40 years--no one knows exactly. Whatever we'll be forced to do later, well, we should be doing that now. We should be moving in that direction now. While we still have enough oil to make a smooth transition to a hydrogen economy.

CON: Dr. Joseph RommDr. Joseph Romm earned his PhD in Physics at MIT and, as acting assistant secretary of energy under President Clinton, oversaw a tenfold increase in funding for hydrogen research. Since, he's done an about-face, writing the book "The Hype About Hydrogen," which questions our government's embrace of hydrogen-fuel-cell vehicles as a near-term strategy. Currently, Dr. Romm is executive director of the Center for Energy & Climate Solutions.Motor Trend: Why are you critical of our government's goal of putting hydrogen-fuel-cell cars on the road as soon as possible?

Joseph Romm: I ran the [Department of Energy's] Hydrogen R&D program, and I believe the [government's] R&D money is well spent. But we need three technological breakthroughs for these vehicles to be realistic in the near term: a fuel-cell-membrane breakthrough, a storage-material breakthrough, and a breakthrough in finding a clean H2 source. Right now, the membrane's durability is about 1000 hours, and it's easily poisoned by such things as sulfur in the air. These are nontrivial problems, and they'll have to be solved while simultaneously reducing the cost of the fuel-cell's membrane by a factor of 100.

Next, the storage issue is a potential show-stopper--it's clear that you can't build a hydrogen economy around high-pressure on-board storage. It would be fatal to H2 cars if they were prematurely introduced into the marketplace with this inadequate storage technology. I don't think your average soccer mom or dad wants to be a foot away from 5000- or 10,000-psi hydrogen canisters--which in industry are treated with great respect, put in separate facilities with blow-out walls, and so forth. We need--according to the American Physical Society--a whole new material for storage, and if you were to ask me how long might it take, the answer is it could take a very long time.

The high cost of H2 fuel is also a big issue; Americans don't like to pay a lot for their transport fuel. However, you couldn't get H2 delivered to the tank of your car in a useable form today for under about $4 per Kg without taxes--and that's assuming the efficiencies of scale afforded by many, many stations. Plus, that's the price of dirty, fossil-fuel-derived H2. The price of green H2 [that is, produced without the emission of CO2] is currently $10 or more. MT: What do you think is the right course?

JR: Compared with hybrids, the fuel-cell car will cost a lot more, have three times the annual fuel bill, a third of the range, limited fueling options, major safety and liability issues, and it won't be greener than the hybrid for two or three more decades. Plus, the hybrid is a moving target that'll keep getting better and better. H2 cars are being pushed by people who haven't done the analysis correctly on the environmental side. And on the policy side, have simply done the analysis wrong. The prospects for the fuel-cell car will only be harmed if it's introduced too soon.

MT: And what do you think will happen?

JR: I think there'll be a flurry of activity, just as there was for electric and natural-gas vehicles, and we'll squander a lot of money relearning the lessons of the past. GM spent a fortune on its EV1--and now almost all of them have been crushed.

Politics And HydrogenA combustible mixOil bad, hydrogen good.That's oversimplifying how the Republican and Democratic platforms treat the promise of hydrogen fuel cells, but not by much. Overall differences in the platforms may be substantial, but when it comes to what many believe is our only foreseeable hope of weaning America away from oil, politicians are quick to take credit for what has already been done and set themselves up as the architects for the future.

Already, we're seeing signs that embracing hydrogen may be, for politicians, the equivalent of baby-kissing. This spring, San Francisco mayor Gavin Newsom held a paper cup beneath the tailpipe of a hydrogen-powered Honda FCX the city had leased, and--as the inevitable cameras rolled--Newsom sipped the condensate that dripped from the Honda's tailpipe.

Neither President Bush nor Senator John Kerry, the apparent Democratic rival for Bush, has sipped tailpipe water yet, but there are still months to go in the campaign.

So far, neither has ventured out much past the party line to distinguish one from the other when it comes to hydrogen power.

Politics And Hydrogen cont... In a state of the union address, Bush announced his $1.2 billion "hydrogen-fuel initiative to reverse the nation's growing dependence on foreign oil," so stated as part of his reelection platform on his Web site. Bush's plans, the platform states via an issue brief, would make it possible for a child born this year to learn to drive in a hydrogen-powered car, "and make it practical and affordable for Americans to choose to use clean, hydrogen-powered vehicles by 2020. "Kerry's official platform contains "a plan to use hydrogen throughout the nation by 2020." Though the published planks of his platform admit that, initially, hydrogen must come from natural gas and coal, it continues, "John Kerry believes that eventually we can build a truly clean and secure economy based on hydrogen--a clean fuel that we can eventually get from our farms, the wind, solar energy, hydropower, and geothermal sources."

What neither the Democrats nor Republicans may be prepared for, though, is the possibility of a major hydrogen-related crisis. It's no secret that, aside from bad weather, more space-shuttle launches have been delayed because of problems with the shuttle's hydrogen fuel (usually leaky tanks) than any other single cause. Using present methods, making, transporting, and storing hydrogen are difficult and potentially dangerous. And though any sort of catastrophic failure may not be likely to occur on a research vehicle constructed by a major manufacturer, with many smaller, private entrepreneurs hopping aboard what California governor Arnold Schwarzenegger calls the "hydrogen highway," few would be surprised if, at some point, something bad happens to a hydrogen-powered vehicle. And to what extent that might set back the progress and cause politicians to back away is anyone's guess.

Not to mention the public-relations challenges involved. The Focus FCV fuel-cell prototype, for instance, currently uses an on-board hydrogen storage tank that can operate at 5000 psi, which gives it a middling sub-200-mile range. Ford engineers would like a 10,000-psi tank. Would you balk at strapping a child seat a few inches away from a tank that holds space-shuttle fuel pressurized to 10,000 pounds per square inch? Accurate or not, we wonder if President Bush or Senator Kerry have been briefed on how to answer that question.

Political futures might well be propelled by hydrogen. But anyone who thinks it'll be easy hasn't been paying attention.

Contemplating a Hydrogen FutureFuel-cell facts abound. As do unanswered questionsIn Jules Verne's 1874 book "The Mysterious Island," a character states: "Yes, my friends, I believe that water will one day be employed as fuel, that hydrogen and oxygen which constitute it, used singly or together, will furnish an inexhaustible source of heat and light, of an intensity of which coal is not capable. "One hundred and thirty years later, Verne's vision no longer seems so fanciful. Politicians and many of their constituents have embraced the hydrogen economy, and our research community has fanned out to patiently untie the numerous knots impeding the technology's progress (supported by enough funding to give them really strong fingers).

Yet the stakes are high and consequences grave if our modern disciples of Verne are wrong. You--or certainly your children--will live through the descent of the petroleum-powered automobile. You and they will live through decades of rising gasoline prices--and possibly through international stresses arising from the struggle over remaining supplies and the consequences of an atmospheric CO2 hangover. We'd encourage all of you to visit the Department of Energy's Web site (www.eia.doe.gov) and search for "long-term world-oil supply" to contemplate for yourself the various estimates of when international oil production is expected to crest and decline.

Our prohydrogen commentaries, offered by Amory B. Lovins and Dennis Weaver, and the contrary opinions provided by Dr. MacCready and Dr. Romm, suggest that there's still considerable disunion over the best course of action here. It seems to us that, despite hydrogen's current momentum, the homework behind it isn't complete. Serious questions remain as to whether fuel cells offer the best or the quickest solution to atmospheric CO2 buildup and a dwindling oil supply. And whether fuel cells are rational from a cost standpoint (an analysis by the Argonne National Laboratory pegs one version of the hydrogen infrastructure, using present technology, at approximately $500 billion dollars). And even whether all of the technical hurdles are resolvable (adequate on-board vehicle storage being A-1 on the list).

We're in the car-testing and magazine-making business, not the future energy and environment business. But the problems facing current fossil-fueled automotive transportation are our problems, too. We'd all be better served if our government assembled the best and brightest of our technical community--people of many perspectives--to sift through all the conflicting proposals and analysis. What's best? What's fantasy? What's possible? Alternate-fuel hybrid technology? Advanced battery-electric vehicles? Bio-diesel? Or, indeed, hydrogen?